SmogRank / History / Country race
Countries, worst air first, day by day
Each country's typical measured city over the 30 days to every day since January 2023, worst first. Press Play to watch the order change, or drag the slider to any day.
The worst countries for PM2.5 over the 7 days to 13 Jun 2026: Chile 42.1 µg/m³, Pakistan 31.7 µg/m³ and India 28.7 µg/m³.
- 1Chile46 cities42.1
- 2Pakistan12 cities31.7
- 3India228 cities28.7
- 4Malawi5 cities26.9
- 5Brazil6 cities23.7
- 6Lebanon3 cities22.3
- 7Peru6 cities21.9
- 8New Zealand6 cities16.5
- 9South Korea135 cities13.2
- 10Senegal4 cities12.5
- 11Kazakhstan4 cities11.4
- 12Thailand77 cities9.5
- 13Mexico47 cities9.3
- 14Japan567 cities7.8
- 15Hungary4 cities, was 137.4
- 16United States829 cities5.9
- 17Taiwan44 cities5.4
- 18Australia37 cities4.5
- 19Canada113 cities4.3
- 20Bulgaria7 cities3.7
+ 3 more countries, 3.7 µg/m³ and below
Not counted on this day, too few cities measured: Austria since 10 Jun 2026, Bosnia and Herzegovina since 10 Jun 2026, Switzerland since 10 Jun 2026 and 27 more countries.
Countries counted each day
A country's number is its typical measured city: the median of its cities' means over the 30 days (a city needs 21 of them measured; 5 of 7 on the 7-day race), shown only with 3 such cities. A country whose monitors go quiet fades out where it stood rather than sliding down, so a gap never reads as cleaner air; "was" beside a city count marks a month after many cities joined or left. Some large countries are thin or missing because their monitors' licences don't allow reuse. How we rank.
Not covered: the government monitoring networks of China and Turkey, which publish only on their own websites; we are building the readers for them. Most cities there are missing from this board, not clean. Why.